1. Field of the Invention
The present invention relates to a test tube holder that is capable of holding a test tube, which keeps a specimen such as blood, in an upright position and is suitable for conveying the test tube.
2. Description of the Related Art
Conventionally test tube holders called columnar racks have been used a lot. The columnar racks each have a columnar base body made of synthetic resin. An engagement groove with which a guide rail of a conveyor belt is engaged and a control groove for controlling the conveyance of a test tube by the conveyor belt are formed on the outer surface of a proximal end portion of the columnar base body such that the test tube can easily be conveyed by the conveyor belt. The columnar base body has a cylindrical hollow for holding and keeping the test tube in an upright position at the core of the columnar base body.
In the conventional columnar rack or test tube holder, the cylindrical hollow is so designed that its size matches that of a specific test tube. Therefore, the columnar rack or the test tube holder cannot be applied to a test tube of size (especially the outside diameter) different from that of the specific test tube.